do not drink alcohol in excess with cialis. side effects may include headache, upset stomach, delayed backache or muscle ache. to avoid long-term injury, seek immediate medical help for an erection lasting more than four hours. if you have any sudden decrease or loss in hearing or vision, or if you have any allergic reactions such as rash, hives, swelling of the lips, tongue or throat, or difficulty breathing or swallowing, stop taking cialis and get medical help right away. ask your doctor about cialis for daily use and a 30-tablet free trial. >>> welcome back. i'm wolf blitzer in boston. happening now a dance instructor wounded in the boston blast vows to dance again and teach our own anderson cooper to dance with her though she no longer has a foot. a shock wave that can be felt from a quarter mile away. cnn shows you up close just how deadly a pressure cooker bomb can be in the hands of a terrorist. and the man accused of sending ricin tainted letters to president obama and other u.s. officials has just been released from f